Upload & Sell: Off
I've had three 5-bay Drobo S's that I use on fast MacPros and laptops for Aperture libraries and Time Machine, and have had a lot of trouble with each of them. Twice the company has replaced one of them, after which I learned that the simple problem was that you cannot dismount them by dragging them to the trash and instead have to use the Drobo dashboard shutdown command, which is ok if a minor nuisance (3 clicks in). If only some of the company's "help" people had known this it would have saved them and me a big hassle. They were nice about helping, but in the end this simple discovery (by me) fixed the main initial problem. However even knowing how to avoid that error, periodically the Drobo shuts down in the middle of an operation and leaves large library files irretrievably corrupted. Then ensues days of copying from backups--terabytes. It's the inconsistency that drives you crazy.
I am happy to report that, in contrast, I have two Pegasus Promise Thunderbolt drives (6 bay) that serve exactly the same functions, and they have worked flawlessly for months. I will never buy another Drobo. I'm happy for the people who have used them successfully; it's clear that these products somehow give people drastically different experiences. If only Drobo could figure out why, and tell us.